When printing different or identical print jobs that are printed in multiple copies, it is desirable to separate said print jobs for the user at the delivery point and to identify where one print job ends and the next one starts. Regarding this, several possibilities for dividing jobs are known.
For example, a dividing sheet can be interposed between print job sheets that are to be placed on top of each other, the format of said dividing sheet being different from the format of the print job sheets that are to be divided, and, in particular, having a larger format. In order to ensure an automated operation of the printing machine, it is practical to transport said dividing sheets out of a feeder that is located in the printing machine. Inasmuch as, however, the dividing sheets must be different from the format of the print jobs to be generated, a feeder is now loaded with dividing sheets that do not participate in the value-added function of the print job, but occupy a feeder and thus lower the productivity of the printing machine because—as a result of the reduced number of usable feeders—the remaining feeders must be loaded more frequently.
Furthermore, there is the possibility of transporting print jobs to an output tray module that consists of several trays arranged in a fan-like manner and that receives a single print job in each tray as is known, for example, from copiers. An output tray that is configured in this manner is significantly more expensive and more susceptible to paper jams than a simple plate-like tray. In addition, due to the number of fan-like arranged plate-like trays in a relatively confined space, their respective stacking height is limited, thus impairing the output of large print jobs in view of the number of pages.
Furthermore, it has been known to move lateral guides of an output tray in lateral direction in order to guide individual print jobs into an end position on the output tray that is different from that of the previous job. On the one hand, such a modification is expensive and, on the other hand, it involves problems in view of the use of an additional substrate and format range of the printing sheet.
Beyond that, it is possible to use another type of output tray, e.g., a rotating or oscillating tray that, due to its principle of operation, allows the sheets to be shifted transversely to their transport direction. These output trays can fulfill the function of the print job division using an offset function, as it were; however, they are significantly more expensive than a plate-like output tray.
Consequently, it is the object of the present invention to simply divide different or identical print jobs that are to be successively fed to a plate-like output tray of a sheet printing machine.